30-year climate normals

Mahaska County Climate and Weather Averages

Hottest month — July

85.5°

average daily high. The coldest month is January, averaging a low of 12.2°F.

Mahaska County gets 38.72" of precipitation a year, and 38% of it falls in Jun, Jul, Aug.

Temperature through the year

Each bar spans the average daily low to the average daily high for that month.

Month	Avg high	Avg low	Precip
January	30.7°	12.2°	1.75"
February	35.9°	15.9°	1.74"
March	49.3°	27.3°	2.15"
April	62.2°	38.1°	3.92"
May	72.2°	50.8°	4.71"
June	81.5°	60.8°	5.18"
July	85.5°	64.8°	4.40"
August	83.8°	62.0°	5.08"
September	77.4°	53.0°	3.56"
October	64.5°	41.2°	2.68"
November	49.3°	28.5°	2.20"
December	36.2°	18.2°	1.35"

Rainfall by month

Precipitation is spread fairly evenly through the year here, with 38% falling in the wettest three months (Jun, Jul, Aug).

January 1.75"

February 1.74"

March 2.15"

April 3.92"

May 4.71"

June 5.18"

July 4.40"

August 5.08"

September 3.56"

October 2.68"

November 2.20"

December 1.35"

Annual total 38.72"

What this climate costs you

Degree days measure how hard a building has to work to stay comfortable. They are the reason two identical houses have very different power bills, and they are the link between the weather here and what you pay every month.

Cooling degree days How much air conditioning the climate demands 958

Heating degree days How much heating the climate demands 6,366

Approximate annual cooling cost At 14.14¢/kWh, Iowa average $135

Approximate annual electric heating cost Lower where heating is gas rather than electric $315

These are rough planning figures from degree days and the state electricity price, not a bill estimate. House size, insulation and fuel type move them a lot. See the full cost of owning a home in Mahaska County, where electricity is one line of eight.

Common questions

What is the weather like in Mahaska County?

Mahaska County averages a high of 85.5°F in July and a low of 12.2°F in January. Annual precipitation is 38.72 inches, with essentially no snow.

When is the rainy season in Mahaska County?

The wettest stretch is Jun, Jul, Aug, which accounts for 38% of the year's precipitation. Precipitation is relatively evenly distributed across the year.

How hot does it get in Mahaska County?

The average daily high in July, the hottest month, is 85.5°F. That drives 958 cooling degree days a year, which is what your air conditioning has to work against.

Does it snow in Mahaska County?

Effectively no. Measurable snowfall is rare in Mahaska County.

Sources

Temperature, precipitation and snowfall normals — NOAA National Centers for Environmental Information, 1991–2020 Monthly Climate Normals, station OSKALOOSA, IA US (USC00136327), 0.8 miles from the county centroid.
Heating and cooling degree days — NOAA, same station and period.
Electricity price — US Energy Information Administration, Electric Power Monthly Table 5.6.A, Iowa residential average.
Wet-season share is the wettest three consecutive months as a percentage of annual precipitation, calculated from the monthly normals.